Chapter 6 PCB Calculators
NI Ultiboard User Manual 6-8 ni.com
You can use the PCB Differential Impedance Calculator to calculate the
following parameters for differential pairs:
• Characteristic Impedance (Zo).
• Per unit length Capacitance (Co).
• Per unit length Inductance (Lo).
• Propogation Delay (tpd).
• Differential Impedance (Zdiff).
The PCB Differential Impedance Calculator supports:
• Microstrip Calculations.
• Embedded Microstrip Calculations.
• Centered Stripline Calculations.
• Asymmetric Stripline Calculations.
Microstrip Calculations
Complete the following steps to perform microstrip differential impedance
calculations:
1. Select Tools»PCB Differential Impedance Calculator.
2. Select Microstrip in the Type drop-down list.
3. In the Input Data area, edit the following fields as desired:
• Input Length Unit—Select mils or millimeters.
• Dielectric Thickness (H)—Refer to the figure below.
• Trace Thickness (T)—Refer to the figure below.
• Trace Width (W)—Refer to the figure below.
• Trace Spacing (S)—Refer to the figure below.
• Relative Permittivity (epsilon r)—Refer to the figure below.
Or
If you wish to define the Characteristic Impedance (Zo) yourself, click
User Defined Zo and edit the following fields as desired:
• Input Length Unit—Select mils or millimeters.
• Dielectric Thickness (H)—Refer to the figure below.
• Trace Spacing (S)—Refer to the figure below.
• Characteristic Impedance (Zo)—Refer to the figure below.
Komentarze do niniejszej Instrukcji